In the plumbing of new homes or buildings, vertical sewer lines must be tested for leaks before the plumbing work can be considered completed. A typical way of testing for such leaks is to place an inflatable bladder in a clean-out of the sewer line near the ground or basement level of the home or building. Then the bladder is inflated to block the sewer line, following which the sewer line above the bladder is filled with water to determine leaks at the joints along the sewer line.
In the past, bladders of this type have been inflated with a conventional, hand-actuated tire pump with the control valve connected to the pump being on the bladder itself. To deflate the bladder after the leak tests have been completed, a workman has had to manually open the valve by depressing the valve stem or otherwise. This causes a slow deflation of the bladder and this is followed by a sudden rush of the water out of the clean-out as the deflating bladder commences to unblock the sewer line. The rushing water usually splashes onto the workman, causing the clothing of the workman to get wet. For this reason, a need has arisen for an improved valve which can permit inflation and rapid deflation of the bladder of the type described without causing a water splashing action when the valve deflates.